1. Field of the Invention
The present invention relates to an electrode type steam vaporizer which feeds steam in a room to increase humidity and can be used for a long time in safety without need for cleaning the electrodes.
2. Description of the Prior Art
Electrode type steam vaporizers usually produce steam by dipping a pair of electrodes into water contained in a container and supplying AC current between the electrodes to heat the water.
The electrode type steam vaporizers humidify with steam whereby the temperature in a room is maintained and steam vaporization can be attained regardless of the room temperature.
In the conventional electrode type steam vaporizers, electrodes made of a metal such as stainless steel or electrodes made of graphite have been used. These electrodes are easily consumed or lack durability. Moreover, calcium oxide etc., is easily deposited on the surface of the electrodes, whereby the electrical conductivity of the surface of the electrodes is deteriorated, cleaning of the surface of the electrodes is required, and maintenance is difficult.
In detail, surfaces of electrodes (anode and cathode) made of graphite or stainless steel are corroded by a chemical reaction which deposits an impurity whereby it is necessary after about ten days to dissemble the electrodes and clean the surfaces of the electrodes. Accordingly, in the conventional electrode type steam vaporizers, an electrode unit or an electrode heater unit is assembled by holding the electrodes in a cylindrical housing having an opening. The unit is assembled in a container so as to be capable of assembly and disassembly therefrom by a simple hand operation such as a turning operation or a sliding operation relative to the container. Water is fed into the container after disassembly of the electrode unit from the container. However, since the electrode unit is easily disassembled to expose it by removing it from the container, a child may disassemble the electrode unit while playing and break the electrode plates. If the electrode unit is disassembled from the container without disconnecting it from the power source, an accident or electric shock may occur.
When the electrode unit is disassembled from the container for feeding water into the container, water on the electrode surface falls down to cause stains on the container. The conventional electrode type steam vaporizer is convenient for disassembling the electrode unit for cleaning of the electrode plates, however, there are various disadvantages as described above.
When the steam vaporizer is used only for few times or a corrosion of the surfaces of the electrodes is not substantially caused, it is seldom necessary to clean the electrodes whereby the simplicity of disassembly and assembly of the electrode unit is not an important function.
When the electrodes are not corroded, it is sufficient to clean them once every six months under normal use. In this case, it is not desirable from the viewpoint of safety to use a steam vaporizer having a common opening for both the connection of an electrode unit and a water inlet and which has a structure permitting easy disassembly of an electrode unit.